JPH0452587B2 - - Google Patents
Info
- Publication number
- JPH0452587B2 JPH0452587B2 JP19990883A JP19990883A JPH0452587B2 JP H0452587 B2 JPH0452587 B2 JP H0452587B2 JP 19990883 A JP19990883 A JP 19990883A JP 19990883 A JP19990883 A JP 19990883A JP H0452587 B2 JPH0452587 B2 JP H0452587B2
- Authority
- JP
- Japan
- Prior art keywords
- insulating layer
- layer
- fluorescent
- grid
- insulating
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000000758 substrate Substances 0.000 claims description 18
- 238000004519 manufacturing process Methods 0.000 claims description 8
- 238000010438 heat treatment Methods 0.000 claims description 6
- 239000011810 insulating material Substances 0.000 claims description 4
- 239000011248 coating agent Substances 0.000 claims 1
- 238000000576 coating method Methods 0.000 claims 1
- 239000000126 substance Substances 0.000 claims 1
- 239000010410 layer Substances 0.000 description 56
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 9
- 238000000034 method Methods 0.000 description 8
- 239000011521 glass Substances 0.000 description 7
- 239000010409 thin film Substances 0.000 description 7
- 239000000463 material Substances 0.000 description 6
- 238000000206 photolithography Methods 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 3
- 238000009413 insulation Methods 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 238000007650 screen-printing Methods 0.000 description 3
- 238000004070 electrodeposition Methods 0.000 description 2
- 239000010408 film Substances 0.000 description 2
- 238000010304 firing Methods 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 238000007639 printing Methods 0.000 description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000012774 insulation material Substances 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229920002120 photoresistant polymer Polymers 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 238000004528 spin coating Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J31/00—Cathode ray tubes; Electron beam tubes
- H01J31/08—Cathode ray tubes; Electron beam tubes having a screen on or from which an image or pattern is formed, picked up, converted, or stored
- H01J31/10—Image or pattern display tubes, i.e. having electrical input and optical output; Flying-spot tubes for scanning purposes
- H01J31/12—Image or pattern display tubes, i.e. having electrical input and optical output; Flying-spot tubes for scanning purposes with luminescent screen
- H01J31/15—Image or pattern display tubes, i.e. having electrical input and optical output; Flying-spot tubes for scanning purposes with luminescent screen with ray or beam selectively directed to luminescent anode segments
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
- H01J29/02—Electrodes; Screens; Mounting, supporting, spacing or insulating thereof
- H01J29/08—Electrodes intimately associated with a screen on or from which an image or pattern is formed, picked-up, converted or stored, e.g. backing-plates for storage tubes or collecting secondary electrons
- H01J29/085—Anode plates, e.g. for screens of flat panel displays
Landscapes
- Cathode-Ray Tubes And Fluorescent Screens For Display (AREA)
Description
【発明の詳細な説明】
〔発明の技術分野〕
本発明は螢光表示管、特にその陽極基板構造に
関するものである。DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a fluorescent display tube, and more particularly to its anode substrate structure.
最近、螢光表示管においても微細でかつ高精度
な表示形態が要求されるようになつている。例え
ば、大形のグラフイツク表示にはドツトマトリツ
クス状に配置した非常に多数の螢光面を精度良く
形成することが必要となつており、この要求を満
たすために、ドツトマトリツクス配置を128×
128、256×256あるいは320×240などとした螢光
表示管が開発されている。
Recently, fine and highly accurate display formats have been required for fluorescent display tubes as well. For example, large-sized graphic displays require highly accurate formation of a large number of fluorescent surfaces arranged in a dot matrix, and to meet this requirement, the dot matrix arrangement has been
Fluorescent display tubes with resolutions of 128, 256 x 256, or 320 x 240 have been developed.
第１図に、従来用いられているこの種の螢光表
示管の陽極基板の構成例を示す。図において、ガ
ラス基板１の上にAl薄膜２からなる配線パター
ンを配置した後、螢光面を形成すべき部分以外の
Al薄膜２を絶縁層３によつて被覆し、さらに、
露出したAl薄膜２上に電着により螢光体を被着
して螢光面４を形成している。なお、５は電子の
供給源であるカソード、６はこのカソード５から
の電子の拡散とスキヤニングを目的として設けら
れるグリツドで、これらグリツド６およびカソー
ド５を陽極基板上方に螢光面４に対向して配置し
た後、周知の管球工程を経て螢光表示管と成す。 FIG. 1 shows an example of the structure of the anode substrate of this type of fluorescent display tube that has been conventionally used. In the figure, after placing a wiring pattern made of an Al thin film 2 on a glass substrate 1,
The Al thin film 2 is covered with an insulating layer 3, and further,
A fluorescent material is deposited on the exposed Al thin film 2 by electrodeposition to form a fluorescent surface 4. Note that 5 is a cathode which is an electron supply source, and 6 is a grid provided for the purpose of diffusing and scanning electrons from this cathode 5. These grid 6 and cathode 5 are placed above the anode substrate and facing the fluorescent surface 4. After arranging the tube, a well-known tube process is carried out to form a fluorescent display tube.
ところで、上記構成において螢光面４が微細か
つ高密度で多数配置される場合、必然的に絶縁層
３も同様に高密度に形成する必要がある。このた
め、従来の絶縁ペーストの厚膜印刷技術による方
法に代り、フオトリソグラフイーを用いた手法に
よつてこの絶縁層３を形成しているが、フオトリ
ソグラフイー法によつて加工可能な絶縁ペースト
はかなり特殊なために、次のような欠点を有して
いる。すなわち、軟化温度が450℃程度と低い低
融点フリツトガラスを主成分としているために、
管球工程時に加熱により軟化し、同じく加熱工程
で膨張したわんだグリツド６がこの軟化した絶縁
材に付着して不良品となる。また、フオトリソグ
ラフイー法によつて行なう関係上、絶縁層の厚み
をあまり厚くできないために、電着法によつて螢
光面を形成した場合、螢光体が当該絶縁層のピン
ホールを介して配線上に付着し、螢光面相互にタ
ツチ不良を生ずる。 By the way, in the above structure, when a large number of fluorescent surfaces 4 are arranged finely and with high density, it is necessary that the insulating layer 3 is similarly formed with high density. For this reason, the insulating layer 3 is formed by a method using photolithography instead of the conventional method using thick film printing technology of insulating paste. is quite special and has the following drawbacks: In other words, since the main component is low-melting fritted glass with a low softening temperature of around 450℃,
The bent grid 6, which is softened by heating during the tube manufacturing process and also expands during the heating process, adheres to this softened insulating material, resulting in a defective product. Furthermore, since the insulating layer cannot be made very thick due to the photolithography method, if a fluorescent surface is formed by electrodeposition, the phosphor will pass through the pinholes in the insulating layer. It adheres to the wiring, causing poor touching between the fluorescent surfaces.
本発明はこのような事情に鑑みてなされたもの
で、その目的は、管球工程時に加熱によりたわん
だグリツドに螢光体を被着しない配線パターンを
被覆する絶縁材が付着したり、絶縁層のピンホー
ルを介する螢光面相互のタツチ不良が発生したり
することのない陽極基板構造を備えた螢光表示管
を提供することにある。
The present invention was made in view of the above circumstances, and its purpose is to prevent the insulating material covering the wiring pattern not covered with the phosphor from adhering to the grid that is bent due to heating during the tube manufacturing process, and the insulating layer An object of the present invention is to provide a fluorescent display tube having an anode substrate structure that does not cause poor contact between fluorescent surfaces due to pinholes.
このような目的を達成するために、本発明は、
絶縁層を二層構造とし、配線パターンに直接接触
する第１層に対し、その上の第２層の軟化温度を
高く、陽極基板の製造工程を除く表示管製造工程
中に加わる加熱温度の上限よりも高く設定したも
のである。以下、実施例を用いて本発明を詳細に
説明する。 In order to achieve such an objective, the present invention
The insulating layer has a two-layer structure, and the softening temperature of the second layer above it is higher than that of the first layer, which is in direct contact with the wiring pattern, and the upper limit of the heating temperature applied during the display tube manufacturing process, excluding the anode substrate manufacturing process. It is set higher than that. Hereinafter, the present invention will be explained in detail using Examples.
第２図は本発明の一実施例を示す断面図で、第
１図と同一記号は対応部分を表わす。異なる点
は、絶縁層３が、Al薄膜２を着接覆つて形成し
た第１層絶縁層３ａと、その上に形成した第２絶
縁層３ｂとの二層構造を有する点である。次に、
このような構造の形成方法の一例を説明する。
FIG. 2 is a sectional view showing one embodiment of the present invention, and the same symbols as in FIG. 1 represent corresponding parts. The difference is that the insulating layer 3 has a two-layer structure consisting of a first insulating layer 3a formed by adhering and covering the Al thin film 2, and a second insulating layer 3b formed thereon. next,
An example of a method for forming such a structure will be explained.
まず、ガラス基板１の上に厚さ1.5〜2.0μｍの
Al薄膜２からなる陽極配線パターンを形成する。
次に、螢光体を被着すべき部分以外のAl薄膜２
の部分に第１層絶縁層３ａを形成する。これは次
のように行なわれる。すなわち、まず基板上に感
光性PVAを主成分とする水溶性のネガレジスト
であるエンコゾルレジストを、スピンコートもし
くはスクリーン印刷法によつて全面に被覆し、乾
燥後フオトマスクを用いて第１層絶縁層３ａを被
覆したい部分以外の部分にエンコゾルレジストを
焼付ける。この後水により現像し、不要のエンコ
ゾルレジストを溶解除去した後、乾燥してレジス
トパターンを得る。次に、基板全面に低融点ガラ
スを主成分とする絶縁ペースト（住友金属鉱山(株)
製＃Ｉ−9404）を約15μｍの厚さにスクリーン印
刷し乾燥する。次いで、上記硬化した水溶性のレ
ジストは溶解するが絶縁層は溶解しない現像液と
して低級アルコールを主成分とする現像液を用い
て現像を行なう。レジストパターンは容易に溶解
しその上の絶縁層と共に剥離する一方、レジスト
パターンが被着していない部分の絶縁層はこの現
像液には不溶のため、基板と強固な付着状態を維
持しており、基板上に所望の形状で残存する。次
に、この基板を焼成炉に入れ、540℃、40分間の
焼成を行なうと絶縁層材料は溶解し、冷却後固化
して強固な第１層絶縁層３ａが形成できる。 First, a film with a thickness of 1.5 to 2.0 μm is placed on the glass substrate 1.
An anode wiring pattern consisting of an Al thin film 2 is formed.
Next, the Al thin film 2 is applied to the area other than the area where the phosphor is to be applied.
A first insulating layer 3a is formed in the portion. This is done as follows. That is, first, Encosol resist, which is a water-soluble negative resist mainly composed of photosensitive PVA, is coated on the entire surface of the substrate by spin coating or screen printing, and after drying, the first layer of insulation is applied using a photomask. An encosol resist is baked on areas other than those desired to be coated with layer 3a. Thereafter, it is developed with water to dissolve and remove unnecessary encosol resist, and then dried to obtain a resist pattern. Next, an insulating paste (Sumitomo Metal Mining Co., Ltd.) mainly composed of low-melting glass was applied to the entire surface of the board.
#I-9404) was screen printed to a thickness of about 15 μm and dried. Next, development is performed using a developer containing lower alcohol as a main component, which dissolves the cured water-soluble resist but does not dissolve the insulating layer. While the resist pattern easily dissolves and peels off together with the insulating layer above it, the insulating layer in the areas where the resist pattern is not adhered is insoluble in this developer, so it maintains a strong adhesion to the substrate. , remains in the desired shape on the substrate. Next, this substrate is placed in a firing furnace and fired at 540° C. for 40 minutes to melt the insulating layer material and solidify after cooling to form a strong first insulating layer 3a.
このようにして第１層絶縁層３ａを完成した
後、この第１層絶縁層３ａの上に第２層絶縁層３
ｂを被覆する。この第２層に用いる材料も、低融
点ガラスを主成分とするフリツトガラスペースト
であるが、第１層のそれよりも軟化温度の高いも
のを用いる。第２層はパターン精度的にはそれ程
高性能のものを要求しなくても良いため、形成方
法としてはスクリーン印刷法を用いることができ
る。というのは、第１層はフオトリソグラフイー
法で形成しており、この層は形状的に非常に高精
度であるが、電着螢光面形状はこの第１層絶縁層
３ａによつて一義的に決定されるからである。も
ちろん、第２層が第１層からはみ出さないように
する配慮は必要であることは言うまでもない。こ
うして第２層絶縁材料の絶縁ペーストをスクリー
ン印刷法により第１層絶層３ａ上に約10〜20μｍ
の厚みに印刷し、焼成して第２層絶縁層３ｂを形
成する。この第２層絶縁層３ｂの形状は、例えば
グリツドがほぼ一方向に細線状に配されている場
合、このグリツドの張り方向と直交する成分を含
むようにすることが、グリツドの第１層絶縁層３
ａへの付着を防止する上で効果的である。 After completing the first insulating layer 3a in this way, a second insulating layer 3 is formed on the first insulating layer 3a.
Cover b. The material used for this second layer is also a fritted glass paste whose main component is low melting point glass, but it has a higher softening temperature than that of the first layer. Since the second layer does not require high performance in terms of pattern accuracy, a screen printing method can be used as a forming method. This is because the first layer is formed by photolithography and has a very high precision in shape, but the shape of the electrodeposited phosphor surface is uniquely determined by the first insulating layer 3a. This is because it is determined based on Of course, it goes without saying that consideration must be taken to prevent the second layer from protruding from the first layer. In this way, the insulation paste of the second layer insulation material is applied to the first insulation layer 3a by screen printing to a thickness of about 10 to 20 μm.
The second insulating layer 3b is formed by printing and firing to a thickness of . The shape of the second layer insulating layer 3b is such that, for example, when the grid is arranged in a thin line shape in approximately one direction, the shape of the first layer insulating layer 3b is such that it includes a component perpendicular to the tension direction of the grid. layer 3
It is effective in preventing adhesion to a.
このように第２層絶縁層３ｂの形成後、螢光体
を電着して螢光面４を形成し、陽極基板を完成す
る。さらにグリツド６およびカソード５を配し、
通常の管球化工程を経て螢光表示管を完成する。
なお、陽極基板製造の表示管製造工程中にかかる
温度の上限は約480℃であるから、その加熱の際
に軟化しないように第２層絶縁層３ｂの軟化点は
それより高くする。 After forming the second insulating layer 3b in this manner, a fluorescent material is electrodeposited to form a fluorescent surface 4, thereby completing the anode substrate. Furthermore, a grid 6 and a cathode 5 are arranged,
A fluorescent display tube is completed through the usual tube forming process.
Incidentally, since the upper limit of the temperature applied during the display tube manufacturing step of manufacturing the anode substrate is about 480° C., the softening point of the second insulating layer 3b is set higher than that so as not to soften during heating.
〔発明の効果〕
以上説明したように、本発明によれば、螢光体
を被着しない配線パターンを被覆する絶縁層を二
層構造とし、上層に軟化点の高い材料を用いたこ
とにより、下層にはフオトリソグラフイー法によ
る精密度加工が可能な材料を用いて電着螢光面の
精度を確保できるとともに、管球化工程中に熱膨
張でたんわんだグリツドが絶縁層に接触しても、
直接接触する第２層絶縁層は軟化しないため絶縁
材料が当該グリツドに付着するのを防止すること
ができる。また、従来上記たわんだグリツドが螢
光体に接触し、グリツドに螢光体が付着して管球
化後にも発光不良となることがあつたが、本発明
によれば螢光面の厚みより絶縁層の厚みが十分に
厚くすることができるため、グリツドが螢光面に
つくことはなくなり、したがつてもれ発光不良を
減らすことができる。さらに、絶縁層が二層構造
であるところから単層のみの場合に比較して相補
効果が生じ、ピンホールはほとんど発生しない。
このため螢光面相互のタツチ不良の発生はほとん
ど皆無となる。[Effects of the Invention] As explained above, according to the present invention, the insulating layer that covers the wiring pattern that is not coated with the phosphor has a two-layer structure, and the upper layer is made of a material with a high softening point. The lower layer is made of a material that can be precisely processed using photolithography to ensure the precision of the electrodeposited fluorescent surface, and also to prevent the grid, which swells due to thermal expansion during the tube formation process, from coming into contact with the insulating layer. too,
Since the second insulating layer in direct contact does not soften, it is possible to prevent insulating material from adhering to the grid. Furthermore, in the past, the bent grid would come into contact with the phosphor and the phosphor would adhere to the grid, resulting in poor light emission even after tube formation, but according to the present invention, the thickness of the phosphor surface Since the thickness of the insulating layer can be made sufficiently thick, the grid will not stick to the fluorescent surface, thereby reducing the occurrence of leakage and poor light emission. Furthermore, since the insulating layer has a two-layer structure, a complementary effect occurs compared to a case where only a single layer is used, and almost no pinholes occur.
Therefore, there is almost no occurrence of poor touching between the phosphor surfaces.
第１図は従来の螢光表示管の陽極基板の構成例
を示す断面図、第２図は本発明の一実施例を示す
断面図である。
１……ガラス基板（絶縁基盤）、２……Al薄膜
（配線パターン）、３……絶縁層、３ａ……第１層
絶縁層、３ｂ……第２層絶縁層、４……螢光面、
５……カソード、６……グリツド。
FIG. 1 is a sectional view showing an example of the structure of a conventional anode substrate of a fluorescent display tube, and FIG. 2 is a sectional view showing an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Glass substrate (insulating base), 2... Al thin film (wiring pattern), 3... Insulating layer, 3a... First layer insulating layer, 3b... Second layer insulating layer, 4... Fluorescent surface ,
5...Cathode, 6...Grid.
Claims (1)
絶縁層で被覆し、露出した配線パターン上に螢光
体を被着して螢光面を形成してなる陽極基板を備
え、上記螢光面に対向してカソードおよび当該螢
光面とカソードとの間にグリツドを配置してなる
螢光表示管において、上記絶縁層を、配線パター
ンに直接接触する第１層とグリツドに対向する第
２層との二層構造とし、第２層の絶縁層を、その
軟化温度が第１層の絶縁層に比較して高くかつ上
記陽極基板の製造工程を除く製造工程中に加わる
加熱温度の上限よりも高い絶縁材料によつて構成
したことを特徴とする螢光表示管。 ２ 第２層の絶縁層を、少なくともグリツドに直
交する成分を含む形状としたことを特徴とする特
許請求の範囲第１項記載の螢光表示管。[Claims] 1. An anode substrate formed by covering a part of a wiring pattern formed on an insulating substrate with an insulating layer and coating a fluorescent substance on the exposed wiring pattern to form a fluorescent surface. In a fluorescent display tube comprising a cathode facing the fluorescent surface and a grid disposed between the fluorescent surface and the cathode, the insulating layer is arranged between the first layer directly contacting the wiring pattern and the grid. The second insulating layer has a softening temperature higher than that of the first insulating layer and is added during the manufacturing process except for the manufacturing process of the anode substrate. A fluorescent display tube characterized in that it is made of an insulating material whose heating temperature is higher than the upper limit. 2. The fluorescent display tube according to claim 1, wherein the second insulating layer has a shape that includes at least a component perpendicular to the grid.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19990883A JPS6093744A (en) | 1983-10-27 | 1983-10-27 | Fluoresent character display tube |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19990883A JPS6093744A (en) | 1983-10-27 | 1983-10-27 | Fluoresent character display tube |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6093744A JPS6093744A (en) | 1985-05-25 |
| JPH0452587B2 true JPH0452587B2 (en) | 1992-08-24 |
Family
ID=16415599
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP19990883A Granted JPS6093744A (en) | 1983-10-27 | 1983-10-27 | Fluoresent character display tube |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6093744A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003100241A (en) * | 2001-09-25 | 2003-04-04 | Noritake Itron Corp | Fluorescent character display tube |
| JP2008031391A (en) * | 2006-08-01 | 2008-02-14 | Jfe Engineering Kk | Apparatus for cleaning platform for coke guide vehicle travel, and coke guide vehicle |
-
1983
- 1983-10-27 JP JP19990883A patent/JPS6093744A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6093744A (en) | 1985-05-25 |
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